Apparatus and Method for Minimizing Transmission Delay in a Data Communication System

1. An apparatus for reducing transmission delay of packet data, the apparatus comprising: a first memory having a first memory area for storing first packet data to be transmitted, and a second memory area for temporarily storing the first packet data and for combining the first packet data with subsequent second packet data; a second memory for receiving and storing a copy of the first packet data temporarily stored in the second memory area, and transmitting the first packet data to a destination according to a link state; and a frame processor for copying the first packet data from the first memory area to the second memory area, storing a copy of the first packet data stored in the second memory area according to a state of the second memory, deleting the first packet data stored in the second memory area when the copy of the first packet data stored in the second memory is transmitted, determining whether packet data combining is possible according to a state of the second memory area, and combining packet data stored in the first memory area with packet data stored in the second memory area and storing the combined packet data in the second memory if packet data combining is possible.

2. The apparatus of claim 1 , further comprising a descriptor indicating an address and a packet data storage state of the second memory.

3. The apparatus of claim 1 , wherein the frame processor flushes packet data stored in the second memory before storing the combined packet data in the second memory, if packet data combining is possible.

4. A method for reducing transmission delay occurring when transmitting packet data to a destination in a transmission module including a first memory having a first memory area for storing packet data to be transmitted and a second memory area for backing up the first memory area by storing a copy of the packet data, a second memory connected to a transmission link, and a frame processor, the method comprising the steps of: storing a copy of the packet data stored in the second memory area according to a state of the second memory; deleting the packet data stored in the second memory area when the copy of the packet data stored in the second memory is transmitted; determining whether packet data combining is possible according to a state of the second memory area; and combining packet data stored in the first memory area with the packet data stored in the second memory area and storing the combined packet data in the second memory if packet data combining is possible.

5. The method of claim 4 , wherein the packet data temporarily stored in the second memory area is deleted if packet data in the second memory is transmitted to a destination.

6. The method of claim 4 , wherein if packet data combining is possible, the packet data stored in the second memory is flushed before the combined packet data is stored in the second memory.

7. The apparatus of claim 1 , wherein the frame processor determines whether the packet data has been transmitted prior to deleting the first packet data stored in the second memory area.

8. The method of claim 4 , wherein deleting the packet data stored in the second memory area comprises if the copy of the packet data stored in the second memory is transmitted the frame processor determines whether the packet data has been transmitted prior to deleting the first packet data stored in the second memory area.